The present disclosure generally relates to resins and resin blends and articles comprising thermoplastic polymers derived from 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimide monomers. Homopolycarbonate and Copolycarbonate resins derived from such monomers generally have a higher Tg and greater oxygen and water permeability than resins derived from the most widely available commercial polycarbonate, bisphenol A (“BPA”) polycarbonate homopolymers. As described herein, it is also possible to make such copolycarbonates with the transparency of polycarbonates and good color (i.e., low yellowness index) provided this monomer is made by a method that achieves sufficient purity. More particularly, the present disclosure relates to resin blends and articles comprising a polycarbonate comprising structural units derived from phenolphthalein derivatives, such as 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimide monomer and an ABS (acrylonitrile-butadiene-styrene) resin. The present disclosure further relates to resins and resin blends and articles comprising a polycarbonate comprising structural units derived from relatively pure 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimide.
It would be desirable to develop a process for preparing relatively pure phenolphthalein derivatives such as 2-hydrocarbyl-3,3-bis(4-hydroxyaryl)phthalimide, which can then in turn be used for producing polycarbonates and other polymers having significant content of structural units derived from this monomer, which polymers also have good color, (e.g., a yellowness index of less than about 10), and reasonably high weight average molecular weight (e.g., at least about 15,000). Further still, there is a need for such resins and resin blends and articles having excellent fire retardance and improved physical properties.